intermolecular forces
forces that occur between molecules
intramolecular forces
forces that occur inside the molecules
dipole-dipole attraction
the attractive force resulting when polar molecules line up such that the positive and negative ends are close to each other
hydrogen bonding
unusually strong dipole-dipole attractions that occur among molecules in which hydrogen is bonded to a highly electronegative atom
london dispersion forces
the relatively weak forces, which exist among noble gas atoms and nonpolar molecules, that involve an accidental dipole that induces a momentary dipole in a neighbor
normal boiling point
the temperature at which the vapor pressure of a liquid is exactly one atmosphere; the boiling temperature under 1 atm of pressure
heating/cooling curve
a plot of temperature versus time for a substance, where energy is added at a constant rate
normal freezing point
the freezing point of a solid at a total pressure of one atmosphere
molar heat of fusion
the energy required to melt 1 mol of a solid
molar heat of vaporization
the energy required to vaporize 1 mol of a liquid
vaporization
the change in state that occurs when a liquid evaporates to form a gas
condensation
the process by which vapor molecules reform a liquid
vapor pressure
the pressure of the vapor over a liquid at equilibrium in a closed container
crystalline solid
a solid characterized by the regular arrangement of its components
ionic solid
a solid containing cations and anions that dissolves in water to give a solution containing the separated ions, which are mobile and thus free to conduct an electric current
molecular solid
a solid composed of small molecules
atomic solid
a solid that contains atoms at the lattice points
electron sea model
pictures a regular array of metal atoms in a "sea" of valence electrons that are shared among the atoms in a nondirectional way and that are quite mobile in the metal crystal
alloy
a substance that contains a mixture of elements and has metallic properties
substitutional alloy
alloy which has atoms of the original metallic solid replaced by other atoms of similar size
interstitial alloy
alloy formed when some of the holes among the closely packed metal atoms are occupied by atoms much smaller than the host atoms
viscosity
the resistance of a liquid to flow
ionic; metallic; covalent
3 types of chemical bonds
ionic bond
the attraction between oppositely charged ions; metal and nonmetal
metallic bond
an attraction in which electrons are shared; most are solid at room temperature
covalent bond
an attraction in which electrons are shared to form the bonds that holds liquids and gases together
surface tension
a property at the surface of a liquid/solid that allows it to resist external forces
volatile liquid
liquid that evaporates easily because the molecules are not strongly attracted to each other
dynamic equilibrium
continually changing balance
hydration
interaction between solute particles and water molecules
anhydrous
without water
amorphous solid
solid that appears to be a solid but does not behave like a solid
metal
a solid that is a good conductor because its valence electrons are free to move